No person can live without coexisting with others. Thus, a person feels a sense of security when forming a group with others and actually feeling that he/she belongs to the group, and desires to feel empathy and a sense of unity with the others belonging to the group.
Accordingly, to obtain the feeling of belonging to a group, or to feel empathy or a sense of unity with others belonging to the group, communication unique to the group may be performed in many cases. A communication tool is used in many cases for this purpose.
In recent years, due to the significant development in the information communication technology, highly sophisticated and multifunctional communication tools, such as mobile phones and smartphones, are becoming widespread (for example, see Patent Document 1).